Above -- forthcoming from Arthur A. Levine Books/Scholastic in April 2012.
But Safe is no longer safe: the night after a frightening encounter in the sewers, Safe's founder Atticus is murdered by the one person Safe ever exiled: mad Corner, whose coup is backed by an army of mindless, whispering shadows.
Only Matthew, Ariel, and a handful of unstable, crippled compatriots escape to the city that cast them out; the dangerous place he knows only as Above. Despite Ariel's increasingly erratic behaviour and with the odds against them, Matthew must find a way to rescue Safe from Corner's occupying army. But as his quest leads him through abandoned asylums and the dregs of urban poverty, Matthew discovers that the histories he's devoted his life to aren't true: Corner's invasion -- and Ariel's terrors – are rooted in a history of Safe much darker and bloodier than Matthew ever imagined.
And even if he manages to save both home and Ariel, he may well lose himself.
Read an interview about writing and selling Above at the Online Writing Workshop for Science Fiction, Fantasy, and Horror.
Or an interview on the same topic as part of Lenore Appelhans's Dystopian August.
Another one, in Spanish, at Soy Cazadora de Sombras y Libros.